Chiral Ureas and Thioureas as Catalysts

A very efficient method for hydrocyanation of aldimines and ketimines has been developed by the Jacobsen group. Chiral urea or thiourea derivatives containing an imine bond of type 9 and 10 were used as organocatalysts [7-13]. The core 

The Jacobsen group also achieved process improvement with respect to catalyst immobilizaion and recycling [10]. In this recycling study a polymer-supported 

It should be added that Jacobsen-type hydrocyanation has already been commercially applied for production of optically active a-amino acids at Chirex (see also Chapter 14). 

A very detailed structural and mechanistic study of this method has also been 

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